Saturday, February 01, 2014

That's the GISS 5-year average. It may look somewhat stuck, although it's important to remember that the now-measly-looking 2002 5-year average was at the time, the highest in the instrumental record. The 1998 5-year average was 0.44 C above the 1951-1980 mean.

The 1979-1986 period was similar to the 2003-2011 time.

The .06 C drop from 1982 to 1984 is interesting - it's the biggest in the instrumental record since the warming restarted in the 1970s. It's a safe bet (as in, I'm willing to bet) that we will never ever get back together with a 5-year average lower than 2002's.

And speaking of betting, while that upstart antipodean Brian Schmidt hogs all the attention, my own 2007 bets plod along to their 10-year through 20-year finish lines. My bet with David Evans wasn't as generous to my side, comparing five year averages to 0.1/decade and 0.15/decade increases (details here from my 2007 post). Last year, fortunately, I was getting creamed with slightly declining average, -0.06/decade. Unfortunately that's now changed to straight zero, which still means I'm getting creamed (temps have to warm substantially or I pay out). If you compare even noisier data of 2012 to 2011, that's a warming rate of 0.2/decade, and I win.

I think the real lesson is not to worry about year-on-year changes. I said in 2007 that my worst-case personal outcome was to lose one bet, void some others, and win most. If the 2017 average is 0.68 or less, then I lose two bets. An increase of 0.09 in six years or less has happened plenty of times in the last 40 years. The warming we've been sticking in the ocean is going to come out at some point, and I think China and India will start to wrestle with their particle emissions soon.

I no longer think I'm safe from losing more than one bet, but unfortunately I feel pretty good about the ultimate outcome.

Actually, your data precisely identifies the warmist case - an increase of about 0.4 degrees C between the eighties and the noughties.

Before that, back to the previous peak in the forties, nothing.

So what caused the increase? As a long time subscriber to your web-site I can fairly say that I have no idea. However, you would have to work very hard with the data to see any correlation with the steady increase in CO2 over the period.

Here is a set of data from the Central England Temperature Record, analysed by successive decades.

Central England Temperature record covers 34 decades, from the end of the first decade in 1679. A warming trend in any period would be indicated by a preponderance of warming decades. Conversely a cooling trend would show as a preponderance of cooling decades. Equal numbers of cooling and warming decades would suggest no trend either way.

The results are illuminating, at least from my sceptical point-of-view.

The first 22 decades, to 1889, show 10 warming and 12 cooling decades, randomly scattered, with negligible overall change.

The next 6 decades to 1949 are all warming as temperatures climb out of the Little Ice Age, from about 9.1 to 9.6 degreesC.

For the last 6 decades, to 2009, we are looking for the impact (or non-impact) of exponentially increasing CO2.

There are 3 warming decades and 3 cooling decades.

Now, admittedly, the temperature increases in the last two decades were significantly greater than any previous, taking the decadal averages above 10 degrees for the first time. The average temperature in the decade ending 2009 was 10.4 degrees C.

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Eli Rabett

Eli Rabett, a not quite failed professorial techno-bunny who finally handed in the keys and retired from his wanna be research university. The students continue to be naive but great people and the administrators continue to vary day-to-day between homicidal and delusional without Eli's help. Eli notices from recent political developments that this behavior is not limited to administrators. His colleagues retain their curious inability to see the holes that they dig for themselves. Prof. Rabett is thankful that they, or at least some of them occasionally heeded his pointing out the implications of the various enthusiasms that rattle around the department and school. Ms. Rabett is thankful that Prof. Rabett occasionally heeds her pointing out that he is nuts.